From 0d32a397887badcd8340eb5711dd1046e3e0d40c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fran=C3=A7ois-Xavier=20de=20Guillebon?=
 <fx@gensdeconfiance.fr>
Date: Tue, 19 Nov 2019 14:54:05 +0100
Subject: [PATCH] Fix CS bis (#1706)

---
 .php_cs.dist                                  |  2 +
 CHANGELOG.md                                  |  1 +
 lib/Elastica/AbstractUpdateAction.php         |  2 +-
 .../Aggregation/AbstractAggregation.php       |  2 +-
 .../Aggregation/AbstractTermsAggregation.php  |  4 +-
 lib/Elastica/Aggregation/AvgBucket.php        |  4 +-
 lib/Elastica/Aggregation/BucketScript.php     |  4 +-
 lib/Elastica/Aggregation/BucketSelector.php   |  8 +--
 lib/Elastica/Aggregation/Derivative.php       |  8 +--
 lib/Elastica/Aggregation/Filter.php           |  7 +-
 lib/Elastica/Aggregation/Filters.php          |  4 +-
 lib/Elastica/Aggregation/GeoDistance.php      |  2 +-
 lib/Elastica/Aggregation/IpRange.php          |  2 +-
 lib/Elastica/Aggregation/Percentiles.php      |  2 +-
 lib/Elastica/Aggregation/Range.php            |  4 +-
 lib/Elastica/Aggregation/ReverseNested.php    |  4 +-
 lib/Elastica/Aggregation/ScriptedMetric.php   |  8 +--
 lib/Elastica/Aggregation/SerialDiff.php       |  6 +-
 lib/Elastica/Aggregation/StatsBucket.php      |  2 +-
 lib/Elastica/Aggregation/SumBucket.php        |  2 +-
 lib/Elastica/Bulk.php                         | 15 ++--
 lib/Elastica/Bulk/Action.php                  |  2 +-
 lib/Elastica/Bulk/Action/AbstractDocument.php |  2 +-
 lib/Elastica/Client.php                       | 70 +++++--------------
 lib/Elastica/Connection/ConnectionPool.php    |  9 +--
 lib/Elastica/Document.php                     |  2 +-
 .../Exception/Connection/GuzzleException.php  |  5 +-
 .../Exception/Connection/HttpException.php    |  2 +-
 .../Exception/ConnectionException.php         |  2 +-
 lib/Elastica/Index.php                        |  2 +-
 lib/Elastica/Multi/Search.php                 |  8 +--
 lib/Elastica/Query/AbstractGeoDistance.php    |  1 -
 lib/Elastica/Query/BoolQuery.php              |  2 -
 lib/Elastica/Query/ConstantScore.php          |  2 +-
 lib/Elastica/Query/FunctionScore.php          | 36 +++++-----
 lib/Elastica/Query/Fuzzy.php                  | 11 ++-
 lib/Elastica/Query/GeoBoundingBox.php         |  6 +-
 lib/Elastica/Query/HasChild.php               |  4 +-
 lib/Elastica/Query/Match.php                  |  2 +-
 lib/Elastica/Query/MatchPhrase.php            |  2 +-
 lib/Elastica/Query/Range.php                  |  2 +-
 lib/Elastica/Query/Regexp.php                 |  4 +-
 lib/Elastica/Query/SpanContaining.php         |  2 +-
 lib/Elastica/Query/SpanFirst.php              |  2 +-
 lib/Elastica/Query/SpanNot.php                |  2 +-
 lib/Elastica/Query/SpanWithin.php             |  2 +-
 lib/Elastica/Query/Wildcard.php               |  2 +-
 lib/Elastica/QueryBuilder.php                 |  2 +-
 lib/Elastica/QueryBuilder/DSL/Aggregation.php | 22 +++---
 lib/Elastica/QueryBuilder/DSL/Query.php       | 45 +++++-------
 lib/Elastica/Request.php                      | 53 +++++---------
 lib/Elastica/ResultSet.php                    |  2 +-
 lib/Elastica/Script/AbstractScript.php        |  2 +-
 lib/Elastica/Script/Script.php                |  7 +-
 lib/Elastica/Script/ScriptId.php              |  3 +-
 lib/Elastica/Scroll.php                       | 18 ++---
 lib/Elastica/Search.php                       | 11 +--
 lib/Elastica/Suggest.php                      |  2 +-
 lib/Elastica/Suggest/AbstractSuggest.php      | 16 ++---
 lib/Elastica/Transport/AbstractTransport.php  | 11 +--
 lib/Elastica/Transport/HttpAdapter.php        |  6 +-
 lib/Elastica/Util.php                         |  4 +-
 test/Elastica/Base.php                        | 20 ++----
 test/Elastica/BasePipeline.php                |  6 +-
 test/Elastica/ErrorsCollector.php             |  2 +-
 test/Elastica/Multi/SearchTest.php            |  2 +-
 66 files changed, 186 insertions(+), 327 deletions(-)

diff --git a/.php_cs.dist b/.php_cs.dist
index 08eb2b6ee4..e813e0306f 100644
--- a/.php_cs.dist
+++ b/.php_cs.dist
@@ -19,6 +19,8 @@ $config = PhpCsFixer\Config::create()
         '@PHPUnit60Migration:risky' => true,
         'php_unit_dedicate_assert' => ['target' => 'newest'],
         'native_function_invocation' => true,
+        'no_alias_functions' => true,
+        'nullable_type_declaration_for_default_null_value' => true,
     ])
 ;
 
diff --git a/CHANGELOG.md b/CHANGELOG.md
index ab509c3093..c55a52ef81 100755
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -22,6 +22,7 @@ All notable changes to this project will be documented in this file based on the
 ### Improvements
 
 * Launch tests with PHP 7.4
+* Added `nullable_type_declaration_for_default_null_value`, `no_alias_functions` CS rules [#1706](https://github.com/ruflin/Elastica/pull/1706)
 
 ### Deprecated
 
diff --git a/lib/Elastica/AbstractUpdateAction.php b/lib/Elastica/AbstractUpdateAction.php
index c87a77a9a4..0b3f83d217 100644
--- a/lib/Elastica/AbstractUpdateAction.php
+++ b/lib/Elastica/AbstractUpdateAction.php
@@ -18,7 +18,7 @@ class AbstractUpdateAction extends Param
     /**
      * Sets the id of the document.
      */
-    public function setId(string $id = null): self
+    public function setId(?string $id = null): self
     {
         return $this->setParam('_id', $id);
     }
diff --git a/lib/Elastica/Aggregation/AbstractAggregation.php b/lib/Elastica/Aggregation/AbstractAggregation.php
index 5d9c43a467..c80fc589ad 100644
--- a/lib/Elastica/Aggregation/AbstractAggregation.php
+++ b/lib/Elastica/Aggregation/AbstractAggregation.php
@@ -132,7 +132,7 @@ public function toArray(): array
             // compensate for class name GlobalAggregation
             $array = ['global' => new \stdClass()];
         }
-        if (\sizeof($this->_aggs)) {
+        if (\count($this->_aggs)) {
             $array['aggs'] = $this->_convertArrayable($this->_aggs);
         }
 
diff --git a/lib/Elastica/Aggregation/AbstractTermsAggregation.php b/lib/Elastica/Aggregation/AbstractTermsAggregation.php
index e4f9739145..16761f8bef 100644
--- a/lib/Elastica/Aggregation/AbstractTermsAggregation.php
+++ b/lib/Elastica/Aggregation/AbstractTermsAggregation.php
@@ -25,7 +25,7 @@ public function setMinimumDocumentCount(int $count): self
      *
      * @return $this
      */
-    public function setInclude(string $pattern, string $flags = null): self
+    public function setInclude(string $pattern, ?string $flags = null): self
     {
         if (null === $flags) {
             return $this->setParam('include', $pattern);
@@ -45,7 +45,7 @@ public function setInclude(string $pattern, string $flags = null): self
      *
      * @return $this
      */
-    public function setExclude(string $pattern, string $flags = null): self
+    public function setExclude(string $pattern, ?string $flags = null): self
     {
         if (null === $flags) {
             return $this->setParam('exclude', $pattern);
diff --git a/lib/Elastica/Aggregation/AvgBucket.php b/lib/Elastica/Aggregation/AvgBucket.php
index 7f1a447751..3f8b25df4a 100644
--- a/lib/Elastica/Aggregation/AvgBucket.php
+++ b/lib/Elastica/Aggregation/AvgBucket.php
@@ -14,7 +14,7 @@ class AvgBucket extends AbstractAggregation
     const DEFAULT_GAP_POLICY_VALUE = 'skip';
     const DEFAULT_FORMAT_VALUE = null;
 
-    public function __construct(string $name, string $bucketsPath = null)
+    public function __construct(string $name, ?string $bucketsPath = null)
     {
         parent::__construct($name);
 
@@ -48,7 +48,7 @@ public function setGapPolicy(string $gapPolicy): self
      *
      * @return $this
      */
-    public function setFormat(string $format = null): self
+    public function setFormat(?string $format = null): self
     {
         return $this->setParam('format', $format);
     }
diff --git a/lib/Elastica/Aggregation/BucketScript.php b/lib/Elastica/Aggregation/BucketScript.php
index 0a65303e7d..568809d0c4 100644
--- a/lib/Elastica/Aggregation/BucketScript.php
+++ b/lib/Elastica/Aggregation/BucketScript.php
@@ -11,7 +11,7 @@
  */
 class BucketScript extends AbstractAggregation
 {
-    public function __construct(string $name, array $bucketsPath = null, string $script = null)
+    public function __construct(string $name, ?array $bucketsPath = null, ?string $script = null)
     {
         parent::__construct($name);
 
@@ -59,7 +59,7 @@ public function setGapPolicy(string $gapPolicy = 'skip'): self
      *
      * @return $this
      */
-    public function setFormat(string $format = null): self
+    public function setFormat(?string $format = null): self
     {
         return $this->setParam('format', $format);
     }
diff --git a/lib/Elastica/Aggregation/BucketSelector.php b/lib/Elastica/Aggregation/BucketSelector.php
index 8a730bc189..5c93739c93 100644
--- a/lib/Elastica/Aggregation/BucketSelector.php
+++ b/lib/Elastica/Aggregation/BucketSelector.php
@@ -9,7 +9,7 @@
  */
 class BucketSelector extends AbstractSimpleAggregation
 {
-    public function __construct(string $name, array $bucketsPath = null, string $script = null)
+    public function __construct(string $name, ?array $bucketsPath = null, ?string $script = null)
     {
         parent::__construct($name);
 
@@ -25,11 +25,9 @@ public function __construct(string $name, array $bucketsPath = null, string $scr
     /**
      * Set the buckets_path for this aggregation.
      *
-     * @param array $bucketsPath
-     *
      * @return $this
      */
-    public function setBucketsPath($bucketsPath)
+    public function setBucketsPath(array $bucketsPath): self
     {
         return $this->setParam('buckets_path', $bucketsPath);
     }
@@ -39,7 +37,7 @@ public function setBucketsPath($bucketsPath)
      *
      * @return $this
      */
-    public function setGapPolicy(string $gapPolicy = 'skip')
+    public function setGapPolicy(string $gapPolicy = 'skip'): self
     {
         return $this->setParam('gap_policy', $gapPolicy);
     }
diff --git a/lib/Elastica/Aggregation/Derivative.php b/lib/Elastica/Aggregation/Derivative.php
index 6eab88a382..4d9983e5ca 100644
--- a/lib/Elastica/Aggregation/Derivative.php
+++ b/lib/Elastica/Aggregation/Derivative.php
@@ -11,7 +11,7 @@
  */
 class Derivative extends AbstractAggregation
 {
-    public function __construct(string $name, string $bucketsPath = null)
+    public function __construct(string $name, ?string $bucketsPath = null)
     {
         parent::__construct($name);
 
@@ -25,7 +25,7 @@ public function __construct(string $name, string $bucketsPath = null)
      *
      * @return $this
      */
-    public function setBucketsPath(string $bucketsPath)
+    public function setBucketsPath(string $bucketsPath): self
     {
         return $this->setParam('buckets_path', $bucketsPath);
     }
@@ -35,7 +35,7 @@ public function setBucketsPath(string $bucketsPath)
      *
      * @return $this
      */
-    public function setGapPolicy(string $gapPolicy = 'skip')
+    public function setGapPolicy(string $gapPolicy = 'skip'): self
     {
         return $this->setParam('gap_policy', $gapPolicy);
     }
@@ -45,7 +45,7 @@ public function setGapPolicy(string $gapPolicy = 'skip')
      *
      * @return $this
      */
-    public function setFormat(string $format)
+    public function setFormat(string $format): self
     {
         return $this->setParam('format', $format);
     }
diff --git a/lib/Elastica/Aggregation/Filter.php b/lib/Elastica/Aggregation/Filter.php
index cbbfadf325..b4767f3e2a 100644
--- a/lib/Elastica/Aggregation/Filter.php
+++ b/lib/Elastica/Aggregation/Filter.php
@@ -12,10 +12,7 @@
  */
 class Filter extends AbstractAggregation
 {
-    /**
-     * @param AbstractQuery $filter
-     */
-    public function __construct(string $name, AbstractQuery $filter = null)
+    public function __construct(string $name, ?AbstractQuery $filter = null)
     {
         parent::__construct($name);
 
@@ -29,7 +26,7 @@ public function __construct(string $name, AbstractQuery $filter = null)
      *
      * @return $this
      */
-    public function setFilter(AbstractQuery $filter)
+    public function setFilter(AbstractQuery $filter): self
     {
         return $this->setParam('filter', $filter);
     }
diff --git a/lib/Elastica/Aggregation/Filters.php b/lib/Elastica/Aggregation/Filters.php
index 683e4c9d3d..4d285e22bf 100644
--- a/lib/Elastica/Aggregation/Filters.php
+++ b/lib/Elastica/Aggregation/Filters.php
@@ -25,11 +25,9 @@ class Filters extends AbstractAggregation
      *
      * If a name is given, it will be added as a key, otherwise considered as an anonymous filter
      *
-     * @param string $name
-     *
      * @return $this
      */
-    public function addFilter(AbstractQuery $filter, string $name = null): self
+    public function addFilter(AbstractQuery $filter, ?string $name = null): self
     {
         $filterArray = [];
 
diff --git a/lib/Elastica/Aggregation/GeoDistance.php b/lib/Elastica/Aggregation/GeoDistance.php
index 4067e3b57a..d019c5fa1d 100644
--- a/lib/Elastica/Aggregation/GeoDistance.php
+++ b/lib/Elastica/Aggregation/GeoDistance.php
@@ -62,7 +62,7 @@ public function setOrigin($origin): self
      *
      * @return $this
      */
-    public function addRange(int $fromValue = null, int $toValue = null): self
+    public function addRange(?int $fromValue = null, ?int $toValue = null): self
     {
         if (null === $fromValue && null === $toValue) {
             throw new InvalidException('Either fromValue or toValue must be set. Both cannot be null.');
diff --git a/lib/Elastica/Aggregation/IpRange.php b/lib/Elastica/Aggregation/IpRange.php
index 6d1dbf7906..b686f1d6e3 100644
--- a/lib/Elastica/Aggregation/IpRange.php
+++ b/lib/Elastica/Aggregation/IpRange.php
@@ -43,7 +43,7 @@ public function setField(string $field): self
      *
      * @return $this
      */
-    public function addRange(string $fromValue = null, string $toValue = null): self
+    public function addRange(?string $fromValue = null, ?string $toValue = null): self
     {
         if (null === $fromValue && null === $toValue) {
             throw new InvalidException('Either fromValue or toValue must be set. Both cannot be null.');
diff --git a/lib/Elastica/Aggregation/Percentiles.php b/lib/Elastica/Aggregation/Percentiles.php
index b0edbec3ef..ec6275eef6 100644
--- a/lib/Elastica/Aggregation/Percentiles.php
+++ b/lib/Elastica/Aggregation/Percentiles.php
@@ -13,7 +13,7 @@ class Percentiles extends AbstractSimpleAggregation
      * @param string $name  the name of this aggregation
      * @param string $field the field on which to perform this aggregation
      */
-    public function __construct(string $name, string $field = null)
+    public function __construct(string $name, ?string $field = null)
     {
         parent::__construct($name);
 
diff --git a/lib/Elastica/Aggregation/Range.php b/lib/Elastica/Aggregation/Range.php
index c8cc2364c9..d66551e5b2 100644
--- a/lib/Elastica/Aggregation/Range.php
+++ b/lib/Elastica/Aggregation/Range.php
@@ -22,7 +22,7 @@ class Range extends AbstractSimpleAggregation
      *
      * @return $this
      */
-    public function addRange($fromValue = null, $toValue = null, string $key = null)
+    public function addRange($fromValue = null, $toValue = null, ?string $key = null): self
     {
         if (null === $fromValue && null === $toValue) {
             throw new InvalidException('Either fromValue or toValue must be set. Both cannot be null.');
@@ -50,7 +50,7 @@ public function addRange($fromValue = null, $toValue = null, string $key = null)
      *
      * @return $this
      */
-    public function setKeyedResponse(bool $keyed = true)
+    public function setKeyedResponse(bool $keyed = true): self
     {
         return $this->setParam('keyed', $keyed);
     }
diff --git a/lib/Elastica/Aggregation/ReverseNested.php b/lib/Elastica/Aggregation/ReverseNested.php
index 611a0d3764..a7b261b4af 100644
--- a/lib/Elastica/Aggregation/ReverseNested.php
+++ b/lib/Elastica/Aggregation/ReverseNested.php
@@ -13,7 +13,7 @@ class ReverseNested extends AbstractAggregation
      * @param string $name The name of this aggregation
      * @param string $path Optional path to the nested object for this aggregation. Defaults to the root of the main document.
      */
-    public function __construct(string $name, string $path = null)
+    public function __construct(string $name, ?string $path = null)
     {
         parent::__construct($name);
 
@@ -27,7 +27,7 @@ public function __construct(string $name, string $path = null)
      *
      * @return $this
      */
-    public function setPath(string $path)
+    public function setPath(string $path): self
     {
         return $this->setParam('path', $path);
     }
diff --git a/lib/Elastica/Aggregation/ScriptedMetric.php b/lib/Elastica/Aggregation/ScriptedMetric.php
index e43b401372..dbae414940 100644
--- a/lib/Elastica/Aggregation/ScriptedMetric.php
+++ b/lib/Elastica/Aggregation/ScriptedMetric.php
@@ -18,10 +18,10 @@ class ScriptedMetric extends AbstractAggregation
      */
     public function __construct(
         string $name,
-        string $initScript = null,
-        string $mapScript = null,
-        string $combineScript = null,
-        string $reduceScript = null
+        ?string $initScript = null,
+        ?string $mapScript = null,
+        ?string $combineScript = null,
+        ?string $reduceScript = null
     ) {
         parent::__construct($name);
         if ($initScript) {
diff --git a/lib/Elastica/Aggregation/SerialDiff.php b/lib/Elastica/Aggregation/SerialDiff.php
index f0020a6e62..aaaf680f33 100644
--- a/lib/Elastica/Aggregation/SerialDiff.php
+++ b/lib/Elastica/Aggregation/SerialDiff.php
@@ -13,7 +13,7 @@ class SerialDiff extends AbstractAggregation
 {
     const DEFAULT_GAP_POLICY_VALUE = 'insert_zero';
 
-    public function __construct(string $name, string $bucketsPath = null)
+    public function __construct(string $name, ?string $bucketsPath = null)
     {
         parent::__construct($name);
 
@@ -55,11 +55,9 @@ public function setGapPolicy(string $gapPolicy): self
     /**
      * Set the format for this aggregation.
      *
-     * @param string $format
-     *
      * @return $this
      */
-    public function setFormat(string $format = null): self
+    public function setFormat(?string $format = null): self
     {
         return $this->setParam('format', $format);
     }
diff --git a/lib/Elastica/Aggregation/StatsBucket.php b/lib/Elastica/Aggregation/StatsBucket.php
index 67478bd135..187441c155 100644
--- a/lib/Elastica/Aggregation/StatsBucket.php
+++ b/lib/Elastica/Aggregation/StatsBucket.php
@@ -11,7 +11,7 @@
  */
 class StatsBucket extends AbstractAggregation
 {
-    public function __construct(string $name, string $bucketsPath = null)
+    public function __construct(string $name, ?string $bucketsPath = null)
     {
         parent::__construct($name);
 
diff --git a/lib/Elastica/Aggregation/SumBucket.php b/lib/Elastica/Aggregation/SumBucket.php
index 4fa7ecdf68..28c378263f 100644
--- a/lib/Elastica/Aggregation/SumBucket.php
+++ b/lib/Elastica/Aggregation/SumBucket.php
@@ -11,7 +11,7 @@
  */
 class SumBucket extends AbstractAggregation
 {
-    public function __construct(string $name, string $bucketsPath = null)
+    public function __construct(string $name, ?string $bucketsPath = null)
     {
         parent::__construct($name);
 
diff --git a/lib/Elastica/Bulk.php b/lib/Elastica/Bulk.php
index bf2f91fdb0..90289459d2 100644
--- a/lib/Elastica/Bulk.php
+++ b/lib/Elastica/Bulk.php
@@ -118,11 +118,9 @@ public function getActions(): array
     }
 
     /**
-     * @param string $opType
-     *
      * @return $this
      */
-    public function addDocument(Document $document, string $opType = null): self
+    public function addDocument(Document $document, ?string $opType = null): self
     {
         $action = AbstractDocumentAction::create($document, $opType);
 
@@ -131,11 +129,10 @@ public function addDocument(Document $document, string $opType = null): self
 
     /**
      * @param Document[] $documents
-     * @param string     $opType
      *
      * @return $this
      */
-    public function addDocuments(array $documents, string $opType = null): self
+    public function addDocuments(array $documents, ?string $opType = null): self
     {
         foreach ($documents as $document) {
             $this->addDocument($document, $opType);
@@ -145,11 +142,9 @@ public function addDocuments(array $documents, string $opType = null): self
     }
 
     /**
-     * @param string $opType
-     *
      * @return $this
      */
-    public function addScript(AbstractScript $script, string $opType = null): self
+    public function addScript(AbstractScript $script, ?string $opType = null): self
     {
         $action = AbstractDocumentAction::create($script, $opType);
 
@@ -158,7 +153,6 @@ public function addScript(AbstractScript $script, string $opType = null): self
 
     /**
      * @param Document[] $scripts
-     * @param string     $opType
      *
      * @return $this
      */
@@ -173,11 +167,10 @@ public function addScripts(array $scripts, $opType = null): self
 
     /**
      * @param \Elastica\Script\AbstractScript|\Elastica\Document|array $data
-     * @param string                                                   $opType
      *
      * @return $this
      */
-    public function addData($data, string $opType = null)
+    public function addData($data, ?string $opType = null)
     {
         if (!\is_array($data)) {
             $data = [$data];
diff --git a/lib/Elastica/Bulk/Action.php b/lib/Elastica/Bulk/Action.php
index cb9fa3c668..4fc5712679 100644
--- a/lib/Elastica/Bulk/Action.php
+++ b/lib/Elastica/Bulk/Action.php
@@ -175,7 +175,7 @@ public function toString(): string
         return $string;
     }
 
-    public static function isValidOpType(string $opType = null): bool
+    public static function isValidOpType(?string $opType = null): bool
     {
         return \in_array($opType, self::$opTypes, true);
     }
diff --git a/lib/Elastica/Bulk/Action/AbstractDocument.php b/lib/Elastica/Bulk/Action/AbstractDocument.php
index 06000fc6e0..4ae9cca76c 100644
--- a/lib/Elastica/Bulk/Action/AbstractDocument.php
+++ b/lib/Elastica/Bulk/Action/AbstractDocument.php
@@ -121,7 +121,7 @@ abstract protected function _getMetadata(AbstractUpdateAction $source): array;
      *
      * @return static
      */
-    public static function create($data, string $opType = null): self
+    public static function create($data, ?string $opType = null): self
     {
         //Check type
         if (!$data instanceof Document && !$data instanceof AbstractScript) {
diff --git a/lib/Elastica/Client.php b/lib/Elastica/Client.php
index 57411279a3..9ea65bf6a0 100644
--- a/lib/Elastica/Client.php
+++ b/lib/Elastica/Client.php
@@ -3,6 +3,7 @@
 namespace Elastica;
 
 use Elastica\Bulk\Action;
+use Elastica\Bulk\ResponseSet;
 use Elastica\Exception\ConnectionException;
 use Elastica\Exception\InvalidException;
 use Elastica\Script\AbstractScript;
@@ -58,13 +59,12 @@ class Client
     /**
      * Creates a new Elastica client.
      *
-     * @param array|string    $config   OPTIONAL Additional config or DSN of options
-     * @param callback|null   $callback OPTIONAL Callback function which can be used to be notified about errors (for example connection down)
-     * @param LoggerInterface $logger
+     * @param array|string  $config   OPTIONAL Additional config or DSN of options
+     * @param callback|null $callback OPTIONAL Callback function which can be used to be notified about errors (for example connection down)
      *
      * @throws \Elastica\Exception\InvalidException
      */
-    public function __construct($config = [], callable $callback = null, LoggerInterface $logger = null)
+    public function __construct($config = [], ?callable $callback = null, ?LoggerInterface $logger = null)
     {
         if (\is_string($config)) {
             $configuration = ClientConfiguration::fromDsn($config);
@@ -76,17 +76,15 @@ public function __construct($config = [], callable $callback = null, LoggerInter
 
         $this->_config = $configuration;
         $this->_callback = $callback;
-        $this->_logger = $logger ?: new NullLogger();
+        $this->_logger = $logger ?? new NullLogger();
 
         $this->_initConnections();
     }
 
     /**
      * Get current version.
-     *
-     * @return string
      */
-    public function getVersion()
+    public function getVersion(): string
     {
         if ($this->_version) {
             return $this->_version;
@@ -221,10 +219,8 @@ public function getConfigValue($keys, $default = null)
      * Returns the index for the given connection.
      *
      * @param string $name Index name to create connection to
-     *
-     * @return \Elastica\Index Index for the given name
      */
-    public function getIndex(string $name)
+    public function getIndex(string $name): Index
     {
         return new Index($this, $name);
     }
@@ -292,10 +288,8 @@ public function removeHeader($header)
      * @param array|\Elastica\Document[] $docs Array of Elastica\Document
      *
      * @throws \Elastica\Exception\InvalidException If docs is empty
-     *
-     * @return \Elastica\Bulk\ResponseSet Response object
      */
-    public function updateDocuments(array $docs, array $requestParams = [])
+    public function updateDocuments(array $docs, array $requestParams = []): ResponseSet
     {
         if (empty($docs)) {
             throw new InvalidException('Array has to consist of at least one element');
@@ -323,10 +317,8 @@ public function updateDocuments(array $docs, array $requestParams = [])
      * @param array|\Elastica\Document[] $docs Array of Elastica\Document
      *
      * @throws \Elastica\Exception\InvalidException If docs is empty
-     *
-     * @return \Elastica\Bulk\ResponseSet Response object
      */
-    public function addDocuments(array $docs, array $requestParams = [])
+    public function addDocuments(array $docs, array $requestParams = []): ResponseSet
     {
         if (empty($docs)) {
             throw new InvalidException('Array has to consist of at least one element');
@@ -351,11 +343,9 @@ public function addDocuments(array $docs, array $requestParams = [])
      * @param string                                                   $index   index to update
      * @param array                                                    $options array of query params to use for query. For possible options check es api
      *
-     * @return \Elastica\Response
-     *
      * @see https://www.elastic.co/guide/en/elasticsearch/reference/current/docs-update.html
      */
-    public function updateDocument($id, $data, $index, array $options = [])
+    public function updateDocument($id, $data, $index, array $options = []): Response
     {
         $endpoint = new Update();
         $endpoint->setID($id);
@@ -420,10 +410,8 @@ public function updateDocument($id, $data, $index, array $options = [])
      * @param array|\Elastica\Document[] $docs
      *
      * @throws \Elastica\Exception\InvalidException
-     *
-     * @return \Elastica\Bulk\ResponseSet
      */
-    public function deleteDocuments(array $docs, array $requestParams = [])
+    public function deleteDocuments(array $docs, array $requestParams = []): ResponseSet
     {
         if (empty($docs)) {
             throw new InvalidException('Array has to consist of at least one element');
@@ -537,10 +525,8 @@ public function setConnections(array $connections)
      * @param string|bool            $routing Optional routing key for all ids
      *
      * @throws \Elastica\Exception\InvalidException
-     *
-     * @return \Elastica\Bulk\ResponseSet Response  object
      */
-    public function deleteIds(array $ids, $index, $routing = false)
+    public function deleteIds(array $ids, $index, $routing = false): ResponseSet
     {
         if (empty($ids)) {
             throw new InvalidException('Array has to consist of at least one id');
@@ -581,14 +567,10 @@ public function deleteIds(array $ids, $index, $routing = false)
      *
      * @see https://www.elastic.co/guide/en/elasticsearch/reference/current/docs-bulk.html
      *
-     * @param array $params Parameter array
-     *
      * @throws \Elastica\Exception\ResponseException
      * @throws \Elastica\Exception\InvalidException
-     *
-     * @return \Elastica\Bulk\ResponseSet Response object
      */
-    public function bulk(array $params)
+    public function bulk(array $params): ResponseSet
     {
         if (empty($params)) {
             throw new InvalidException('Array has to consist of at least one param');
@@ -613,10 +595,8 @@ public function bulk(array $params)
      * @param string       $contentType Content-Type sent with this request
      *
      * @throws Exception\ConnectionException|Exception\ClientException
-     *
-     * @return Response Response object
      */
-    public function request($path, $method = Request::GET, $data = [], array $query = [], $contentType = Request::DEFAULT_CONTENT_TYPE)
+    public function request(string $path, string $method = Request::GET, $data = [], array $query = [], string $contentType = Request::DEFAULT_CONTENT_TYPE): Response
     {
         $connection = $this->getConnection();
         $request = $this->_lastRequest = new Request($path, $method, $data, $query, $connection, $contentType);
@@ -651,10 +631,8 @@ public function request($path, $method = Request::GET, $data = [], array $query
 
     /**
      * Makes calls to the elasticsearch server with usage official client Endpoint.
-     *
-     * @return Response
      */
-    public function requestEndpoint(AbstractEndpoint $endpoint)
+    public function requestEndpoint(AbstractEndpoint $endpoint): Response
     {
         return $this->request(
             \ltrim($endpoint->getURI(), '/'),
@@ -669,11 +647,9 @@ public function requestEndpoint(AbstractEndpoint $endpoint)
      *
      * @param array $args OPTIONAL Optional arguments
      *
-     * @return \Elastica\Response Response object
-     *
      * @see https://www.elastic.co/guide/en/elasticsearch/reference/current/indices-forcemerge.html
      */
-    public function forcemergeAll($args = [])
+    public function forcemergeAll($args = []): Response
     {
         $endpoint = new ForceMerge();
         $endpoint->setParams($args);
@@ -684,27 +660,19 @@ public function forcemergeAll($args = [])
     /**
      * Refreshes all search indices.
      *
-     * @return \Elastica\Response Response object
-     *
      * @see https://www.elastic.co/guide/en/elasticsearch/reference/current/indices-refresh.html
      */
-    public function refreshAll()
+    public function refreshAll(): Response
     {
         return $this->requestEndpoint(new Refresh());
     }
 
-    /**
-     * @return Request|null
-     */
-    public function getLastRequest()
+    public function getLastRequest(): ?Request
     {
         return $this->_lastRequest;
     }
 
-    /**
-     * @return Response|null
-     */
-    public function getLastResponse()
+    public function getLastResponse(): ?Response
     {
         return $this->_lastResponse;
     }
diff --git a/lib/Elastica/Connection/ConnectionPool.php b/lib/Elastica/Connection/ConnectionPool.php
index 135cf38926..5023385bf5 100644
--- a/lib/Elastica/Connection/ConnectionPool.php
+++ b/lib/Elastica/Connection/ConnectionPool.php
@@ -26,19 +26,14 @@ class ConnectionPool
     protected $_strategy;
 
     /**
-     * @var callable Function called on connection fail
+     * @var callable|null Function called on connection fail
      */
     protected $_callback;
 
-    /**
-     * @param callback|null $callback
-     */
-    public function __construct(array $connections, StrategyInterface $strategy, callable $callback = null)
+    public function __construct(array $connections, StrategyInterface $strategy, ?callable $callback = null)
     {
         $this->_connections = $connections;
-
         $this->_strategy = $strategy;
-
         $this->_callback = $callback;
     }
 
diff --git a/lib/Elastica/Document.php b/lib/Elastica/Document.php
index 0d28038cb4..c615c65532 100644
--- a/lib/Elastica/Document.php
+++ b/lib/Elastica/Document.php
@@ -40,7 +40,7 @@ class Document extends AbstractUpdateAction
      * @param array|string $data  Data array
      * @param Index|string $index Index name
      */
-    public function __construct(string $id = null, $data = [], $index = '')
+    public function __construct(?string $id = null, $data = [], $index = '')
     {
         $this->setId($id);
         $this->setData($data);
diff --git a/lib/Elastica/Exception/Connection/GuzzleException.php b/lib/Elastica/Exception/Connection/GuzzleException.php
index 013875b345..da3fb6a3c6 100644
--- a/lib/Elastica/Exception/Connection/GuzzleException.php
+++ b/lib/Elastica/Exception/Connection/GuzzleException.php
@@ -20,10 +20,7 @@ class GuzzleException extends ConnectionException
      */
     protected $_guzzleException;
 
-    /**
-     * @param Request $request
-     */
-    public function __construct(TransferException $guzzleException, Request $request = null, Response $response = null)
+    public function __construct(TransferException $guzzleException, ?Request $request = null, ?Response $response = null)
     {
         $this->_guzzleException = $guzzleException;
         $message = $this->getErrorMessage($this->getGuzzleException());
diff --git a/lib/Elastica/Exception/Connection/HttpException.php b/lib/Elastica/Exception/Connection/HttpException.php
index 7c88195545..98eac8dd3b 100644
--- a/lib/Elastica/Exception/Connection/HttpException.php
+++ b/lib/Elastica/Exception/Connection/HttpException.php
@@ -27,7 +27,7 @@ class HttpException extends ConnectionException
      * @param Request  $request
      * @param Response $response
      */
-    public function __construct($error, Request $request = null, Response $response = null)
+    public function __construct($error, ?Request $request = null, ?Response $response = null)
     {
         $this->_error = $error;
 
diff --git a/lib/Elastica/Exception/ConnectionException.php b/lib/Elastica/Exception/ConnectionException.php
index 5a9c5e2b96..99f1680cd3 100644
--- a/lib/Elastica/Exception/ConnectionException.php
+++ b/lib/Elastica/Exception/ConnectionException.php
@@ -25,7 +25,7 @@ class ConnectionException extends \RuntimeException implements ExceptionInterfac
     /**
      * Construct Exception.
      */
-    public function __construct(string $message, Request $request = null, Response $response = null)
+    public function __construct(string $message, ?Request $request = null, ?Response $response = null)
     {
         $this->_request = $request;
         $this->_response = $response;
diff --git a/lib/Elastica/Index.php b/lib/Elastica/Index.php
index 0be3256ac9..4d617ae093 100644
--- a/lib/Elastica/Index.php
+++ b/lib/Elastica/Index.php
@@ -462,7 +462,7 @@ public function exists(): bool
      *
      * @return Search
      */
-    public function createSearch($query = '', $options = null, BuilderInterface $builder = null)
+    public function createSearch($query = '', $options = null, ?BuilderInterface $builder = null)
     {
         $search = new Search($this->getClient(), $builder);
         $search->addIndex($this);
diff --git a/lib/Elastica/Multi/Search.php b/lib/Elastica/Multi/Search.php
index 4b048c64eb..8a4b444776 100644
--- a/lib/Elastica/Multi/Search.php
+++ b/lib/Elastica/Multi/Search.php
@@ -49,10 +49,8 @@ class Search
 
     /**
      * Constructs search object.
-     *
-     * @param MultiBuilderInterface $builder
      */
-    public function __construct(Client $client, MultiBuilderInterface $builder = null)
+    public function __construct(Client $client, ?MultiBuilderInterface $builder = null)
     {
         $this->_builder = $builder ?? new MultiBuilder();
         $this->_client = $client;
@@ -74,11 +72,9 @@ public function clearSearches(): self
     }
 
     /**
-     * @param string $key
-     *
      * @return $this
      */
-    public function addSearch(BaseSearch $search, string $key = null): self
+    public function addSearch(BaseSearch $search, ?string $key = null): self
     {
         if ($key) {
             $this->_searches[$key] = $search;
diff --git a/lib/Elastica/Query/AbstractGeoDistance.php b/lib/Elastica/Query/AbstractGeoDistance.php
index f11de3193e..4803bbb681 100644
--- a/lib/Elastica/Query/AbstractGeoDistance.php
+++ b/lib/Elastica/Query/AbstractGeoDistance.php
@@ -57,7 +57,6 @@ abstract class AbstractGeoDistance extends AbstractQuery
     /**
      * Create GeoDistance object.
      *
-     * @param string       $key      Key
      * @param array|string $location Location as array or geohash: array('lat' => 48.86, 'lon' => 2.35) OR 'drm3btev3e86'
      *
      * @internal param string $distance Distance
diff --git a/lib/Elastica/Query/BoolQuery.php b/lib/Elastica/Query/BoolQuery.php
index 9c8df96c63..49223c9242 100644
--- a/lib/Elastica/Query/BoolQuery.php
+++ b/lib/Elastica/Query/BoolQuery.php
@@ -52,8 +52,6 @@ public function addMustNot($args): self
     /**
      * Sets the filter.
      *
-     * @param AbstractQuery $filter Filter object
-     *
      * @return $this
      */
     public function addFilter(AbstractQuery $filter): self
diff --git a/lib/Elastica/Query/ConstantScore.php b/lib/Elastica/Query/ConstantScore.php
index 34d860c721..9a5be6978b 100644
--- a/lib/Elastica/Query/ConstantScore.php
+++ b/lib/Elastica/Query/ConstantScore.php
@@ -14,7 +14,7 @@ class ConstantScore extends AbstractQuery
     /**
      * Construct constant score query.
      */
-    public function __construct(AbstractQuery $filter = null)
+    public function __construct(?AbstractQuery $filter = null)
     {
         if (null !== $filter) {
             $this->setFilter($filter);
diff --git a/lib/Elastica/Query/FunctionScore.php b/lib/Elastica/Query/FunctionScore.php
index bb7d1e52c7..adf5d0d46c 100644
--- a/lib/Elastica/Query/FunctionScore.php
+++ b/lib/Elastica/Query/FunctionScore.php
@@ -73,8 +73,8 @@ public function setQuery(AbstractQuery $query): self
     public function addFunction(
         string $functionType,
         $functionParams,
-        AbstractQuery $filter = null,
-        float $weight = null
+        ?AbstractQuery $filter = null,
+        ?float $weight = null
     ): self {
         $function = [
             $functionType => $functionParams,
@@ -102,7 +102,7 @@ public function addFunction(
      *
      * @return $this
      */
-    public function addScriptScoreFunction(AbstractScript $script, AbstractQuery $filter = null, float $weight = null)
+    public function addScriptScoreFunction(AbstractScript $script, ?AbstractQuery $filter = null, ?float $weight = null)
     {
         return $this->addFunction('script_score', $script, $filter, $weight);
     }
@@ -127,11 +127,11 @@ public function addDecayFunction(
         string $field,
         string $origin,
         string $scale,
-        string $offset = null,
-        float $decay = null,
-        float $weight = null,
-        AbstractQuery $filter = null,
-        string $multiValueMode = null
+        ?string $offset = null,
+        ?float $decay = null,
+        ?float $weight = null,
+        ?AbstractQuery $filter = null,
+        ?string $multiValueMode = null
     ) {
         $functionParams = [
             $field => [
@@ -158,11 +158,11 @@ public function addDecayFunction(
      */
     public function addFieldValueFactorFunction(
         string $field,
-        float $factor = null,
-        string $modifier = null,
-        float $missing = null,
-        float $weight = null,
-        AbstractQuery $filter = null
+        ?float $factor = null,
+        ?string $modifier = null,
+        ?float $missing = null,
+        ?float $weight = null,
+        ?AbstractQuery $filter = null
     ): self {
         $functionParams = [
             'field' => $field,
@@ -189,7 +189,7 @@ public function addFieldValueFactorFunction(
      *
      * @return $this
      */
-    public function addWeightFunction(float $weight, AbstractQuery $filter = null): self
+    public function addWeightFunction(float $weight, ?AbstractQuery $filter = null): self
     {
         return $this->addFunction('weight', $weight, $filter);
     }
@@ -206,9 +206,9 @@ public function addWeightFunction(float $weight, AbstractQuery $filter = null):
      */
     public function addRandomScoreFunction(
         int $seed,
-        AbstractQuery $filter = null,
-        float $weight = null,
-        string $field = null
+        ?AbstractQuery $filter = null,
+        ?float $weight = null,
+        ?string $field = null
     ): self {
         $functionParams = [
             'seed' => $seed,
@@ -260,7 +260,7 @@ public function setBoostMode(string $mode = self::BOOST_MODE_MULTIPLY): self
      *
      * @return $this
      */
-    public function setRandomScore(int $seed = null): self
+    public function setRandomScore(?int $seed = null): self
     {
         $seedParam = new \stdClass();
         if (null !== $seed) {
diff --git a/lib/Elastica/Query/Fuzzy.php b/lib/Elastica/Query/Fuzzy.php
index 3a4ed5dc91..3357e8ee79 100644
--- a/lib/Elastica/Query/Fuzzy.php
+++ b/lib/Elastica/Query/Fuzzy.php
@@ -16,10 +16,9 @@ class Fuzzy extends AbstractQuery
     /**
      * Construct a fuzzy query.
      *
-     * @param string $fieldName Field name
-     * @param string $value     String to search for
+     * @param string $value String to search for
      */
-    public function __construct(string $fieldName = null, string $value = null)
+    public function __construct(?string $fieldName = null, ?string $value = null)
     {
         if (null !== $fieldName && null !== $value) {
             $this->setField($fieldName, $value);
@@ -29,8 +28,7 @@ public function __construct(string $fieldName = null, string $value = null)
     /**
      * Set field for fuzzy query.
      *
-     * @param string $fieldName Field name
-     * @param string $value     String to search for
+     * @param string $value String to search for
      *
      * @return $this
      */
@@ -49,8 +47,7 @@ public function setField(string $fieldName, string $value): self
     /**
      * Set optional parameters on the existing query.
      *
-     * @param string $option option name
-     * @param mixed  $value  Value of the parameter
+     * @param mixed $value Value of the parameter
      *
      * @return $this
      */
diff --git a/lib/Elastica/Query/GeoBoundingBox.php b/lib/Elastica/Query/GeoBoundingBox.php
index 59d61bc51e..743fccac58 100644
--- a/lib/Elastica/Query/GeoBoundingBox.php
+++ b/lib/Elastica/Query/GeoBoundingBox.php
@@ -16,8 +16,7 @@ class GeoBoundingBox extends AbstractQuery
     /**
      * Construct BoundingBoxQuery.
      *
-     * @param string $key         Key
-     * @param array  $coordinates Array with top left coordinate as first and bottom right coordinate as second element
+     * @param array $coordinates Array with top left coordinate as first and bottom right coordinate as second element
      */
     public function __construct(string $key, array $coordinates)
     {
@@ -27,8 +26,7 @@ public function __construct(string $key, array $coordinates)
     /**
      * Add coordinates.
      *
-     * @param string $key         Key
-     * @param array  $coordinates Array with top left coordinate as first and bottom right coordinate as second element
+     * @param array $coordinates Array with top left coordinate as first and bottom right coordinate as second element
      *
      * @throws \Elastica\Exception\InvalidException If $coordinates doesn't have two elements
      *
diff --git a/lib/Elastica/Query/HasChild.php b/lib/Elastica/Query/HasChild.php
index 99768ec411..026055d171 100644
--- a/lib/Elastica/Query/HasChild.php
+++ b/lib/Elastica/Query/HasChild.php
@@ -19,7 +19,7 @@ class HasChild extends AbstractQuery
      * @param string|BaseQuery|AbstractQuery $query
      * @param string                         $type  Parent document type
      */
-    public function __construct($query, string $type = null)
+    public function __construct($query, ?string $type = null)
     {
         $this->setType($type);
         $this->setQuery($query);
@@ -44,7 +44,7 @@ public function setQuery($query): self
      *
      * @return $this
      */
-    public function setType(string $type = null): self
+    public function setType(?string $type = null): self
     {
         return $this->setParam('type', $type);
     }
diff --git a/lib/Elastica/Query/Match.php b/lib/Elastica/Query/Match.php
index 090d2b93c4..4a70993be4 100644
--- a/lib/Elastica/Query/Match.php
+++ b/lib/Elastica/Query/Match.php
@@ -24,7 +24,7 @@ class Match extends AbstractQuery
      * @param string $field
      * @param mixed  $values
      */
-    public function __construct(string $field = null, $values = null)
+    public function __construct(?string $field = null, $values = null)
     {
         if (null !== $field && null !== $values) {
             $this->setParam($field, $values);
diff --git a/lib/Elastica/Query/MatchPhrase.php b/lib/Elastica/Query/MatchPhrase.php
index 5daa3f90a1..74ae2e8e0c 100644
--- a/lib/Elastica/Query/MatchPhrase.php
+++ b/lib/Elastica/Query/MatchPhrase.php
@@ -16,7 +16,7 @@ class MatchPhrase extends AbstractQuery
      * @param string $field
      * @param mixed  $values
      */
-    public function __construct(string $field = null, $values = null)
+    public function __construct(?string $field = null, $values = null)
     {
         if (null !== $field && null !== $values) {
             $this->setParam($field, $values);
diff --git a/lib/Elastica/Query/Range.php b/lib/Elastica/Query/Range.php
index b50c22704b..a36855723e 100644
--- a/lib/Elastica/Query/Range.php
+++ b/lib/Elastica/Query/Range.php
@@ -17,7 +17,7 @@ class Range extends AbstractQuery
      * @param string $fieldName Field name
      * @param array  $args      Field arguments
      */
-    public function __construct(string $fieldName = null, array $args = [])
+    public function __construct(?string $fieldName = null, array $args = [])
     {
         if ($fieldName) {
             $this->addField($fieldName, $args);
diff --git a/lib/Elastica/Query/Regexp.php b/lib/Elastica/Query/Regexp.php
index 275094357f..89a3c3bb4e 100644
--- a/lib/Elastica/Query/Regexp.php
+++ b/lib/Elastica/Query/Regexp.php
@@ -18,7 +18,7 @@ class Regexp extends AbstractQuery
      * @param string $value OPTIONAL Regexp value
      * @param float  $boost OPTIONAL Boost value (default = 1)
      */
-    public function __construct(string $key = '', string $value = null, float $boost = 1.0)
+    public function __construct(string $key = '', ?string $value = null, float $boost = 1.0)
     {
         if (!empty($key)) {
             $this->setValue($key, $value, $boost);
@@ -32,7 +32,7 @@ public function __construct(string $key = '', string $value = null, float $boost
      *
      * @return $this
      */
-    public function setValue(string $key, string $value = null, float $boost = 1.0)
+    public function setValue(string $key, ?string $value = null, float $boost = 1.0)
     {
         return $this->setParam($key, ['value' => $value, 'boost' => $boost]);
     }
diff --git a/lib/Elastica/Query/SpanContaining.php b/lib/Elastica/Query/SpanContaining.php
index 8914a9816f..913d4fc4df 100644
--- a/lib/Elastica/Query/SpanContaining.php
+++ b/lib/Elastica/Query/SpanContaining.php
@@ -17,7 +17,7 @@ class SpanContaining extends AbstractSpanQuery
      * @param AbstractSpanQuery $little OPTIONAL
      * @param AbstractSpanQuery $big    OPTIONAL
      */
-    public function __construct(AbstractSpanQuery $little = null, AbstractSpanQuery $big = null)
+    public function __construct(?AbstractSpanQuery $little = null, ?AbstractSpanQuery $big = null)
     {
         if (null !== $little) {
             $this->setLittle($little);
diff --git a/lib/Elastica/Query/SpanFirst.php b/lib/Elastica/Query/SpanFirst.php
index 1fb512290c..c913b98855 100644
--- a/lib/Elastica/Query/SpanFirst.php
+++ b/lib/Elastica/Query/SpanFirst.php
@@ -19,7 +19,7 @@ class SpanFirst extends AbstractSpanQuery
      * @param AbstractQuery|array $match
      * @param int                 $end
      */
-    public function __construct($match = null, int $end = null)
+    public function __construct($match = null, ?int $end = null)
     {
         if (null !== $match) {
             $this->setMatch($match);
diff --git a/lib/Elastica/Query/SpanNot.php b/lib/Elastica/Query/SpanNot.php
index 25578a4a10..4947d52b95 100644
--- a/lib/Elastica/Query/SpanNot.php
+++ b/lib/Elastica/Query/SpanNot.php
@@ -17,7 +17,7 @@ class SpanNot extends AbstractSpanQuery
      * @param AbstractSpanQuery $include
      * @param AbstractSpanQuery $exclude
      */
-    public function __construct(AbstractSpanQuery $include = null, AbstractSpanQuery $exclude = null)
+    public function __construct(?AbstractSpanQuery $include = null, ?AbstractSpanQuery $exclude = null)
     {
         if (null !== $include) {
             $this->setInclude($include);
diff --git a/lib/Elastica/Query/SpanWithin.php b/lib/Elastica/Query/SpanWithin.php
index 01b019036c..579bf2eb44 100644
--- a/lib/Elastica/Query/SpanWithin.php
+++ b/lib/Elastica/Query/SpanWithin.php
@@ -17,7 +17,7 @@ class SpanWithin extends AbstractSpanQuery
      * @param AbstractSpanQuery $little
      * @param AbstractSpanQuery $big
      */
-    public function __construct(AbstractSpanQuery $little = null, AbstractSpanQuery $big = null)
+    public function __construct(?AbstractSpanQuery $little = null, ?AbstractSpanQuery $big = null)
     {
         if (null !== $little) {
             $this->setLittle($little);
diff --git a/lib/Elastica/Query/Wildcard.php b/lib/Elastica/Query/Wildcard.php
index e7249720d4..8ce6e481f9 100644
--- a/lib/Elastica/Query/Wildcard.php
+++ b/lib/Elastica/Query/Wildcard.php
@@ -18,7 +18,7 @@ class Wildcard extends AbstractQuery
      * @param string $value OPTIONAL Wildcard value
      * @param float  $boost OPTIONAL Boost value (default = 1)
      */
-    public function __construct(string $key = '', string $value = null, float $boost = 1.0)
+    public function __construct(string $key = '', ?string $value = null, float $boost = 1.0)
     {
         if (!empty($key)) {
             $this->setValue($key, $value, $boost);
diff --git a/lib/Elastica/QueryBuilder.php b/lib/Elastica/QueryBuilder.php
index 6d3f768dd3..ebbb8c4872 100644
--- a/lib/Elastica/QueryBuilder.php
+++ b/lib/Elastica/QueryBuilder.php
@@ -27,7 +27,7 @@ class QueryBuilder
     /**
      * Constructor.
      */
-    public function __construct(Version $version = null)
+    public function __construct(?Version $version = null)
     {
         $this->_version = $version ?? new Version\Latest();
 
diff --git a/lib/Elastica/QueryBuilder/DSL/Aggregation.php b/lib/Elastica/QueryBuilder/DSL/Aggregation.php
index f32e05bcd2..aa48473cf2 100644
--- a/lib/Elastica/QueryBuilder/DSL/Aggregation.php
+++ b/lib/Elastica/QueryBuilder/DSL/Aggregation.php
@@ -90,7 +90,7 @@ public function sum(string $name): Sum
      *
      * @see https://www.elastic.co/guide/en/elasticsearch/reference/current/search-aggregations-pipeline-sum-bucket-aggregation.html
      */
-    public function sum_bucket(string $name, string $bucketsPath = null): SumBucket
+    public function sum_bucket(string $name, ?string $bucketsPath = null): SumBucket
     {
         return new SumBucket($name, $bucketsPath);
     }
@@ -110,7 +110,7 @@ public function avg(string $name): Avg
      *
      * @see https://www.elastic.co/guide/en/elasticsearch/reference/current/search-aggregations-pipeline-avg-bucket-aggregation.html
      */
-    public function avg_bucket(string $name, string $bucketsPath = null): AvgBucket
+    public function avg_bucket(string $name, ?string $bucketsPath = null): AvgBucket
     {
         return new AvgBucket($name, $bucketsPath);
     }
@@ -153,7 +153,7 @@ public function value_count(string $name, string $field): ValueCount
      * @param string $name  the name of this aggregation
      * @param string $field the field on which to perform this aggregation
      */
-    public function percentiles(string $name, string $field = null): Percentiles
+    public function percentiles(string $name, ?string $field = null): Percentiles
     {
         return new Percentiles($name, $field);
     }
@@ -209,10 +209,10 @@ public function top_hits(string $name): TopHits
      */
     public function scripted_metric(
         string $name,
-        string $initScript = null,
-        string $mapScript = null,
-        string $combineScript = null,
-        string $reduceScript = null
+        ?string $initScript = null,
+        ?string $mapScript = null,
+        ?string $combineScript = null,
+        ?string $reduceScript = null
     ): ScriptedMetric {
         return new ScriptedMetric($name, $initScript, $mapScript, $combineScript, $reduceScript);
     }
@@ -234,7 +234,7 @@ public function global_agg(string $name): GlobalAggregation
      *
      * @param AbstractQuery $filter
      */
-    public function filter(string $name, AbstractQuery $filter = null): Filter
+    public function filter(string $name, ?AbstractQuery $filter = null): Filter
     {
         return new Filter($name, $filter);
     }
@@ -279,7 +279,7 @@ public function nested(string $name, string $path): Nested
      * @param string $name The name of this aggregation
      * @param string $path Optional path to the nested object for this aggregation. Defaults to the root of the main document.
      */
-    public function reverse_nested(string $name, string $path = null): ReverseNested
+    public function reverse_nested(string $name, ?string $path = null): ReverseNested
     {
         return new ReverseNested($name, $path);
     }
@@ -406,7 +406,7 @@ public function geohash_grid(string $name, string $field): GeohashGrid
      *
      * @see https://www.elastic.co/guide/en/elasticsearch/reference/current/search-aggregations-pipeline-bucket-script-aggregation.html
      */
-    public function bucket_script(string $name, array $bucketsPath = null, string $script = null): BucketScript
+    public function bucket_script(string $name, ?array $bucketsPath = null, ?string $script = null): BucketScript
     {
         return new BucketScript($name, $bucketsPath, $script);
     }
@@ -416,7 +416,7 @@ public function bucket_script(string $name, array $bucketsPath = null, string $s
      *
      * @see https://www.elastic.co/guide/en/elasticsearch/reference/current/search-aggregations-pipeline-serialdiff-aggregation.html
      */
-    public function serial_diff(string $name, string $bucketsPath = null): SerialDiff
+    public function serial_diff(string $name, ?string $bucketsPath = null): SerialDiff
     {
         return new SerialDiff($name, $bucketsPath);
     }
diff --git a/lib/Elastica/QueryBuilder/DSL/Query.php b/lib/Elastica/QueryBuilder/DSL/Query.php
index 4e71ad557e..228ac31f17 100644
--- a/lib/Elastica/QueryBuilder/DSL/Query.php
+++ b/lib/Elastica/QueryBuilder/DSL/Query.php
@@ -70,10 +70,9 @@ public function getType(): string
      *
      * @see https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-match-query.html
      *
-     * @param string $field
-     * @param mixed  $values
+     * @param mixed $values
      */
-    public function match(string $field = null, $values = null): Match
+    public function match(?string $field = null, $values = null): Match
     {
         return new Match($field, $values);
     }
@@ -125,7 +124,7 @@ public function common_terms(string $field, string $query, float $cutoffFrequenc
      *
      * @see https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-constant-score-query.html
      */
-    public function constant_score(AbstractQuery $filter = null): ConstantScore
+    public function constant_score(?AbstractQuery $filter = null): ConstantScore
     {
         return new ConstantScore($filter);
     }
@@ -155,10 +154,9 @@ public function function_score(): FunctionScore
      *
      * @see https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-fuzzy-query.html
      *
-     * @param string $fieldName Field name
-     * @param string $value     String to search for
+     * @param string $value String to search for
      */
-    public function fuzzy(string $fieldName = null, string $value = null): Fuzzy
+    public function fuzzy(?string $fieldName = null, ?string $value = null): Fuzzy
     {
         return new Fuzzy($fieldName, $value);
     }
@@ -213,7 +211,7 @@ public function geo_shape()
      * @param string|BaseQuery|AbstractQuery $query
      * @param string                         $type  Parent document type
      */
-    public function has_child($query, string $type = null): HasChild
+    public function has_child($query, ?string $type = null): HasChild
     {
         return new HasChild($query, $type);
     }
@@ -266,7 +264,7 @@ public function match_none(): MatchNone
      *
      * @see https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-match-query-phrase.html
      */
-    public function match_phrase(string $field = null, $values = null): MatchPhrase
+    public function match_phrase(?string $field = null, $values = null): MatchPhrase
     {
         return new MatchPhrase($field, $values);
     }
@@ -276,7 +274,7 @@ public function match_phrase(string $field = null, $values = null): MatchPhrase
      *
      * @see https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-match-query-phrase-prefix.html
      */
-    public function match_phrase_prefix(string $field = null, $values = null): MatchPhrasePrefix
+    public function match_phrase_prefix(?string $field = null, $values = null): MatchPhrasePrefix
     {
         return new MatchPhrasePrefix($field, $values);
     }
@@ -303,8 +301,6 @@ public function nested(): Nested
 
     /**
      * @param int|string $id
-     *
-     * @return ParentId ParentId
      */
     public function parent_id(string $type, $id, bool $ignoreUnmapped = false): ParentId
     {
@@ -349,10 +345,8 @@ public function simple_query_string(string $query, array $fields = []): SimpleQu
      * range query.
      *
      * @see https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-range-query.html
-     *
-     * @param string $fieldName
      */
-    public function range(string $fieldName = null, array $args = []): Range
+    public function range(?string $fieldName = null, array $args = []): Range
     {
         return new Range($fieldName, $args);
     }
@@ -360,11 +354,9 @@ public function range(string $fieldName = null, array $args = []): Range
     /**
      * regexp query.
      *
-     * @param string $value
-     *
      * @see https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-regexp-query.html
      */
-    public function regexp(string $key = '', string $value = null, float $boost = 1.0): Regexp
+    public function regexp(string $key = '', ?string $value = null, float $boost = 1.0): Regexp
     {
         return new Regexp($key, $value, $boost);
     }
@@ -373,11 +365,10 @@ public function regexp(string $key = '', string $value = null, float $boost = 1.
      * span first query.
      *
      * @param AbstractQuery|array $match
-     * @param int                 $end
      *
      * @see https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-span-first-query.html
      */
-    public function span_first($match = null, int $end = null): SpanFirst
+    public function span_first($match = null, ?int $end = null): SpanFirst
     {
         return new SpanFirst($match, $end);
     }
@@ -409,7 +400,7 @@ public function span_near(array $clauses = [], int $slop = 1, bool $inOrder = fa
      *
      * @see https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-span-not-query.html
      */
-    public function span_not(AbstractSpanQuery $include = null, AbstractSpanQuery $exclude = null): SpanNot
+    public function span_not(?AbstractSpanQuery $include = null, ?AbstractSpanQuery $exclude = null): SpanNot
     {
         return new SpanNot($include, $exclude);
     }
@@ -439,7 +430,7 @@ public function span_term(array $term = []): SpanTerm
      *
      * @see https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-span-containing-query.html
      */
-    public function span_containing(AbstractSpanQuery $little = null, AbstractSpanQuery $big = null): SpanContaining
+    public function span_containing(?AbstractSpanQuery $little = null, ?AbstractSpanQuery $big = null): SpanContaining
     {
         return new SpanContaining($little, $big);
     }
@@ -449,7 +440,7 @@ public function span_containing(AbstractSpanQuery $little = null, AbstractSpanQu
      *
      * @see https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-span-within-query.html
      */
-    public function span_within(AbstractSpanQuery $little = null, AbstractSpanQuery $big = null): SpanWithin
+    public function span_within(?AbstractSpanQuery $little = null, ?AbstractSpanQuery $big = null): SpanWithin
     {
         return new SpanWithin($little, $big);
     }
@@ -479,11 +470,11 @@ public function terms(string $key = '', array $terms = []): Terms
      *
      * @see https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-wildcard-query.html
      *
-     * @param string $key   OPTIONAL Wildcard key
-     * @param string $value OPTIONAL Wildcard value
-     * @param float  $boost OPTIONAL Boost value (default = 1)
+     * @param string      $key   OPTIONAL Wildcard key
+     * @param string|null $value OPTIONAL Wildcard value
+     * @param float       $boost OPTIONAL Boost value (default = 1)
      */
-    public function wildcard(string $key = '', string $value = null, float $boost = 1.0): Wildcard
+    public function wildcard(string $key = '', ?string $value = null, float $boost = 1.0): Wildcard
     {
         return new Wildcard($key, $value, $boost);
     }
diff --git a/lib/Elastica/Request.php b/lib/Elastica/Request.php
index 6044c42bf9..8c26983daf 100644
--- a/lib/Elastica/Request.php
+++ b/lib/Elastica/Request.php
@@ -27,16 +27,13 @@ class Request extends Param
     /**
      * Construct.
      *
-     * @param string     $path        Request path
-     * @param string     $method      OPTIONAL Request method (use const's) (default = self::GET)
-     * @param array      $data        OPTIONAL Data array
-     * @param array      $query       OPTIONAL Query params
-     * @param Connection $connection
-     * @param string     $contentType Content-Type sent with this request
-     *
-     * @return \Elastica\Request OPTIONAL Connection object
+     * @param string $path        Request path
+     * @param string $method      OPTIONAL Request method (use const's) (default = self::GET)
+     * @param array  $data        OPTIONAL Data array
+     * @param array  $query       OPTIONAL Query params
+     * @param string $contentType Content-Type sent with this request
      */
-    public function __construct($path, $method = self::GET, $data = [], array $query = [], Connection $connection = null, $contentType = self::DEFAULT_CONTENT_TYPE)
+    public function __construct(string $path, string $method = self::GET, $data = [], array $query = [], ?Connection $connection = null, string $contentType = self::DEFAULT_CONTENT_TYPE)
     {
         $this->setPath($path);
         $this->setMethod($method);
@@ -52,21 +49,17 @@ public function __construct($path, $method = self::GET, $data = [], array $query
     /**
      * Sets the request method. Use one of the for consts.
      *
-     * @param string $method Request method
-     *
      * @return $this
      */
-    public function setMethod($method)
+    public function setMethod(string $method)
     {
         return $this->setParam('method', $method);
     }
 
     /**
      * Get request method.
-     *
-     * @return string Request method
      */
-    public function getMethod()
+    public function getMethod(): string
     {
         return $this->getParam('method');
     }
@@ -96,21 +89,17 @@ public function getData()
     /**
      * Sets the request path.
      *
-     * @param string $path Request path
-     *
      * @return $this
      */
-    public function setPath($path)
+    public function setPath(string $path)
     {
         return $this->setParam('path', $path);
     }
 
     /**
      * Return request path.
-     *
-     * @return string Request path
      */
-    public function getPath()
+    public function getPath(): string
     {
         return $this->getParam('path');
     }
@@ -120,7 +109,7 @@ public function getPath()
      *
      * @return array Query params
      */
-    public function getQuery()
+    public function getQuery(): array
     {
         return $this->getParam('query');
     }
@@ -134,8 +123,6 @@ public function setQuery(array $query = [])
     }
 
     /**
-     * @param \Elastica\Connection $connection
-     *
      * @return $this
      */
     public function setConnection(Connection $connection)
@@ -148,13 +135,11 @@ public function setConnection(Connection $connection)
     /**
      * Return Connection Object.
      *
-     * @throws Exception\InvalidException If no valid connection was setted
-     *
-     * @return \Elastica\Connection
+     * @throws Exception\InvalidException If no valid connection was set
      */
-    public function getConnection()
+    public function getConnection(): Connection
     {
-        if (empty($this->_connection)) {
+        if (null === $this->_connection) {
             throw new InvalidException('No valid connection object set');
         }
 
@@ -163,10 +148,8 @@ public function getConnection()
 
     /**
      * Set the Content-Type of this request.
-     *
-     * @param string $contentType
      */
-    public function setContentType($contentType)
+    public function setContentType(string $contentType)
     {
         return $this->setParam('contentType', $contentType);
     }
@@ -174,17 +157,15 @@ public function setContentType($contentType)
     /**
      * Get the Content-Type of this request.
      */
-    public function getContentType()
+    public function getContentType(): string
     {
         return $this->getParam('contentType');
     }
 
     /**
      * Sends request to server.
-     *
-     * @return \Elastica\Response Response object
      */
-    public function send()
+    public function send(): Response
     {
         $transport = $this->getConnection()->getTransportObject();
 
diff --git a/lib/Elastica/ResultSet.php b/lib/Elastica/ResultSet.php
index af66de11e4..c67ed4edcb 100644
--- a/lib/Elastica/ResultSet.php
+++ b/lib/Elastica/ResultSet.php
@@ -241,7 +241,7 @@ public function count()
      */
     public function countSuggests()
     {
-        return \sizeof($this->getSuggests());
+        return \count($this->getSuggests());
     }
 
     /**
diff --git a/lib/Elastica/Script/AbstractScript.php b/lib/Elastica/Script/AbstractScript.php
index 2d1087fb99..dd01c9e0ca 100644
--- a/lib/Elastica/Script/AbstractScript.php
+++ b/lib/Elastica/Script/AbstractScript.php
@@ -87,7 +87,7 @@ private static function _createFromArray(array $data)
      * @param string|null $lang       Script language, see constants
      * @param string|null $documentId Document ID the script action should be performed on (only relevant in update context)
      */
-    public function __construct(array $params = null, string $lang = null, string $documentId = null)
+    public function __construct(?array $params = null, ?string $lang = null, ?string $documentId = null)
     {
         if ($params) {
             $this->setParams($params);
diff --git a/lib/Elastica/Script/Script.php b/lib/Elastica/Script/Script.php
index 55111c1329..d6dee4645a 100644
--- a/lib/Elastica/Script/Script.php
+++ b/lib/Elastica/Script/Script.php
@@ -22,17 +22,14 @@ class Script extends AbstractScript
      * @param string      $scriptCode Script source code
      * @param string|null $documentId Document ID the script action should be performed on (only relevant in update context)
      */
-    public function __construct(string $scriptCode, array $params = null, string $lang = null, string $documentId = null)
+    public function __construct(string $scriptCode, ?array $params = null, ?string $lang = null, ?string $documentId = null)
     {
         parent::__construct($params, $lang, $documentId);
 
         $this->setScript($scriptCode);
     }
 
-    /**
-     * @return $this
-     */
-    public function setScript(string $scriptCode): Script
+    public function setScript(string $scriptCode): self
     {
         $this->_scriptCode = $scriptCode;
 
diff --git a/lib/Elastica/Script/ScriptId.php b/lib/Elastica/Script/ScriptId.php
index 6c613586e5..f5e746760b 100644
--- a/lib/Elastica/Script/ScriptId.php
+++ b/lib/Elastica/Script/ScriptId.php
@@ -18,10 +18,9 @@ class ScriptId extends AbstractScript
     private $_scriptId;
 
     /**
-     * @param string      $scriptId   Script ID
      * @param string|null $documentId Document ID the script action should be performed on (only relevant in update context)
      */
-    public function __construct(string $scriptId, array $params = null, string $lang = null, string $documentId = null)
+    public function __construct(string $scriptId, ?array $params = null, ?string $lang = null, ?string $documentId = null)
     {
         parent::__construct($params, $lang, $documentId);
 
diff --git a/lib/Elastica/Scroll.php b/lib/Elastica/Scroll.php
index 0022337240..e1377b9e9a 100644
--- a/lib/Elastica/Scroll.php
+++ b/lib/Elastica/Scroll.php
@@ -44,10 +44,8 @@ class Scroll implements \Iterator
 
     /**
      * Constructor.
-     *
-     * @param string $expiryTime
      */
-    public function __construct(Search $search, $expiryTime = '1m')
+    public function __construct(Search $search, string $expiryTime = '1m')
     {
         $this->_search = $search;
         $this->expiryTime = $expiryTime;
@@ -57,10 +55,8 @@ public function __construct(Search $search, $expiryTime = '1m')
      * Returns current result set.
      *
      * @see http://php.net/manual/en/iterator.current.php
-     *
-     * @return ResultSet
      */
-    public function current()
+    public function current(): ?ResultSet
     {
         return $this->_currentResultSet;
     }
@@ -92,10 +88,8 @@ public function next()
      * Returns scroll id.
      *
      * @see http://php.net/manual/en/iterator.key.php
-     *
-     * @return string
      */
-    public function key()
+    public function key(): ?string
     {
         return $this->_nextScrollId;
     }
@@ -104,10 +98,8 @@ public function key()
      * Returns true if current result set contains at least one hit.
      *
      * @see http://php.net/manual/en/iterator.valid.php
-     *
-     * @return bool
      */
-    public function valid()
+    public function valid(): bool
     {
         return null !== $this->_nextScrollId;
     }
@@ -117,7 +109,7 @@ public function valid()
      *
      * @see http://php.net/manual/en/iterator.rewind.php
      */
-    public function rewind()
+    public function rewind(): void
     {
         // reset state
         $this->_options = [null, null];
diff --git a/lib/Elastica/Search.php b/lib/Elastica/Search.php
index 943ee66d1d..0244d9fc0c 100644
--- a/lib/Elastica/Search.php
+++ b/lib/Elastica/Search.php
@@ -77,11 +77,8 @@ class Search
 
     /**
      * Constructs search object.
-     *
-     * @param \Elastica\Client $client  Client object
-     * @param BuilderInterface $builder
      */
-    public function __construct(Client $client, BuilderInterface $builder = null)
+    public function __construct(Client $client, ?BuilderInterface $builder = null)
     {
         $this->_builder = $builder ?: new DefaultBuilder();
         $this->_client = $client;
@@ -441,12 +438,8 @@ public function setSuggest(Suggest $suggest)
      * Returns the Scroll Iterator.
      *
      * @see Scroll
-     *
-     * @param string $expiryTime
-     *
-     * @return Scroll
      */
-    public function scroll($expiryTime = '1m')
+    public function scroll(string $expiryTime = '1m'): Scroll
     {
         return new Scroll($this, $expiryTime);
     }
diff --git a/lib/Elastica/Suggest.php b/lib/Elastica/Suggest.php
index 0cef285e59..52a84e3419 100644
--- a/lib/Elastica/Suggest.php
+++ b/lib/Elastica/Suggest.php
@@ -15,7 +15,7 @@ class Suggest extends Param
     /**
      * @param AbstractSuggest $suggestion
      */
-    public function __construct(AbstractSuggest $suggestion = null)
+    public function __construct(?AbstractSuggest $suggestion = null)
     {
         if (!\is_null($suggestion)) {
             $this->addSuggestion($suggestion);
diff --git a/lib/Elastica/Suggest/AbstractSuggest.php b/lib/Elastica/Suggest/AbstractSuggest.php
index 5b6511b1d4..0ee209de37 100644
--- a/lib/Elastica/Suggest/AbstractSuggest.php
+++ b/lib/Elastica/Suggest/AbstractSuggest.php
@@ -27,7 +27,7 @@ public function __construct(string $name, string $field)
      *
      * @return $this
      */
-    public function setText(string $text): AbstractSuggest
+    public function setText(string $text): self
     {
         return $this->_setRawParam('text', $text);
     }
@@ -37,7 +37,7 @@ public function setText(string $text): AbstractSuggest
      *
      * @return $this
      */
-    public function setPrefix(string $prefix): AbstractSuggest
+    public function setPrefix(string $prefix): self
     {
         return $this->_setRawParam('prefix', $prefix);
     }
@@ -47,7 +47,7 @@ public function setPrefix(string $prefix): AbstractSuggest
      *
      * @return $this
      */
-    public function setRegex(string $regex): AbstractSuggest
+    public function setRegex(string $regex): self
     {
         return $this->_setRawParam('regex', $regex);
     }
@@ -58,7 +58,7 @@ public function setRegex(string $regex): AbstractSuggest
      *
      * @return $this
      */
-    public function setRegexOptions(array $value): AbstractSuggest
+    public function setRegexOptions(array $value): self
     {
         return $this->setParam('regex', $value);
     }
@@ -66,7 +66,7 @@ public function setRegexOptions(array $value): AbstractSuggest
     /**
      * @return $this
      */
-    public function setField(string $field): AbstractSuggest
+    public function setField(string $field): self
     {
         return $this->setParam('field', $field);
     }
@@ -74,7 +74,7 @@ public function setField(string $field): AbstractSuggest
     /**
      * @return $this
      */
-    public function setSize(int $size): AbstractSuggest
+    public function setSize(int $size): self
     {
         return $this->setParam('size', $size);
     }
@@ -84,7 +84,7 @@ public function setSize(int $size): AbstractSuggest
      *
      * @return $this
      */
-    public function setShardSize(int $size): AbstractSuggest
+    public function setShardSize(int $size): self
     {
         return $this->setParam('shard_size', $size);
     }
@@ -99,7 +99,7 @@ public function setShardSize(int $size): AbstractSuggest
      *
      * @return $this
      */
-    public function setName(string $name): AbstractSuggest
+    public function setName(string $name): self
     {
         if (empty($name)) {
             throw new InvalidException('Suggest name has to be set');
diff --git a/lib/Elastica/Transport/AbstractTransport.php b/lib/Elastica/Transport/AbstractTransport.php
index 2e0ea6f0b5..f25ffc4d34 100644
--- a/lib/Elastica/Transport/AbstractTransport.php
+++ b/lib/Elastica/Transport/AbstractTransport.php
@@ -22,27 +22,20 @@ abstract class AbstractTransport extends Param
 
     /**
      * Construct transport.
-     *
-     * @param Connection $connection Connection object
      */
-    public function __construct(Connection $connection = null)
+    public function __construct(?Connection $connection = null)
     {
         if ($connection) {
             $this->setConnection($connection);
         }
     }
 
-    /**
-     * @return Connection Connection object
-     */
     public function getConnection(): Connection
     {
         return $this->_connection;
     }
 
     /**
-     * @param Connection $connection Connection object
-     *
      * @return $this
      */
     public function setConnection(Connection $connection): AbstractTransport
@@ -57,8 +50,6 @@ public function setConnection(Connection $connection): AbstractTransport
      *
      * @param Request $request Request object
      * @param array   $params  Hostname, port, path, ...
-     *
-     * @return Response Response object
      */
     abstract public function exec(Request $request, array $params): Response;
 
diff --git a/lib/Elastica/Transport/HttpAdapter.php b/lib/Elastica/Transport/HttpAdapter.php
index dcd3986d0d..62e9eb48ab 100644
--- a/lib/Elastica/Transport/HttpAdapter.php
+++ b/lib/Elastica/Transport/HttpAdapter.php
@@ -29,10 +29,8 @@ class HttpAdapter extends AbstractTransport
 
     /**
      * Construct transport.
-     *
-     * @param Connection $connection
      */
-    public function __construct(Connection $connection = null, HttpAdapterInterface $httpAdapter)
+    public function __construct(?Connection $connection = null, HttpAdapterInterface $httpAdapter)
     {
         parent::__construct($connection);
         $this->httpAdapter = $httpAdapter;
@@ -48,8 +46,6 @@ public function __construct(Connection $connection = null, HttpAdapterInterface
      * @throws \Elastica\Exception\ConnectionException
      * @throws \Elastica\Exception\ResponseException
      * @throws \Elastica\Exception\Connection\HttpException
-     *
-     * @return \Elastica\Response Response object
      */
     public function exec(ElasticaRequest $elasticaRequest, array $params): Response
     {
diff --git a/lib/Elastica/Util.php b/lib/Elastica/Util.php
index 8925b554ae..5c9c8dcc94 100644
--- a/lib/Elastica/Util.php
+++ b/lib/Elastica/Util.php
@@ -198,11 +198,9 @@ public static function convertDate($date)
      *
      * Converts it to the lucene format, including the appropriate TimeZone
      *
-     * @param bool $includeTimezone
-     *
      * @return string
      */
-    public static function convertDateTimeObject(\DateTime $dateTime, $includeTimezone = true)
+    public static function convertDateTimeObject(\DateTime $dateTime, bool $includeTimezone = true)
     {
         $formatString = 'Y-m-d\TH:i:s'.(true === $includeTimezone ? 'P' : '\Z');
         $string = $dateTime->format($formatString);
diff --git a/test/Elastica/Base.php b/test/Elastica/Base.php
index 8e2a0eec34..f789dbca91 100644
--- a/test/Elastica/Base.php
+++ b/test/Elastica/Base.php
@@ -58,13 +58,9 @@ protected function finishCollectErrors()
     }
 
     /**
-     * @param array           $params   Additional configuration params. Host and Port are already set
-     * @param callback        $callback
-     * @param LoggerInterface $logger
-     *
-     * @return Client
+     * @param array $params Additional configuration params. Host and Port are already set
      */
-    protected function _getClient(array $params = [], $callback = null, LoggerInterface $logger = null)
+    protected function _getClient(array $params = [], ?callable $callback = null, ?LoggerInterface $logger = null): Client
     {
         $config = [
             'host' => $this->_getHost(),
@@ -92,27 +88,21 @@ protected function _getPort()
         return \getenv('ES_PORT') ?: Connection::DEFAULT_PORT;
     }
 
-    /**
-     * @return string Proxy url string
-     */
-    protected function _getProxyUrl()
+    protected function _getProxyUrl(): string
     {
         $proxyHost = \getenv('PROXY_HOST') ?: Connection::DEFAULT_HOST;
 
         return 'http://'.$proxyHost.':12345';
     }
 
-    /**
-     * @return string Proxy url string to proxy which returns 403
-     */
-    protected function _getProxyUrl403()
+    protected function _getProxyUrl403(): string
     {
         $proxyHost = \getenv('PROXY_HOST') ?: Connection::DEFAULT_HOST;
 
         return 'http://'.$proxyHost.':12346';
     }
 
-    protected function _createIndex(string $name = null, bool $delete = true, int $shards = 1): Index
+    protected function _createIndex(?string $name = null, bool $delete = true, int $shards = 1): Index
     {
         if (null === $name) {
             $name = \preg_replace('/[^a-z]/i', '', \strtolower(\get_called_class()).\uniqid());
diff --git a/test/Elastica/BasePipeline.php b/test/Elastica/BasePipeline.php
index 3133e973c2..8496e9889d 100644
--- a/test/Elastica/BasePipeline.php
+++ b/test/Elastica/BasePipeline.php
@@ -9,12 +9,8 @@ class BasePipeline extends BaseTest
 {
     /**
      * Create Pipeline object.
-     *
-     * @param string $id
-     *
-     * @return Pipeline
      */
-    protected function _createPipeline(string $id = null, string $description = '')
+    protected function _createPipeline(?string $id = null, string $description = ''): Pipeline
     {
         if (\is_null($id)) {
             $id = \preg_replace('/[^a-z]/i', '', \strtolower(\get_called_class()).\uniqid());
diff --git a/test/Elastica/ErrorsCollector.php b/test/Elastica/ErrorsCollector.php
index 39a586d3a5..c2bc0d62c4 100644
--- a/test/Elastica/ErrorsCollector.php
+++ b/test/Elastica/ErrorsCollector.php
@@ -18,7 +18,7 @@ class ErrorsCollector
      */
     private $testCase;
 
-    public function __construct(TestCase $testCase = null)
+    public function __construct(?TestCase $testCase = null)
     {
         $this->testCase = $testCase;
     }
diff --git a/test/Elastica/Multi/SearchTest.php b/test/Elastica/Multi/SearchTest.php
index eac9bb06b6..e335a639b8 100644
--- a/test/Elastica/Multi/SearchTest.php
+++ b/test/Elastica/Multi/SearchTest.php
@@ -15,7 +15,7 @@
 
 class SearchTest extends BaseTest
 {
-    protected function _createIndex(string $name = null, bool $delete = true, int $shards = 1): Index
+    protected function _createIndex(?string $name = null, bool $delete = true, int $shards = 1): Index
     {
         $client = $this->_getClient();